Moisture-curing composition with good adhesive properties

ABSTRACT

A moisture-curing composition that is liquid at ambient temperature and optionally highly viscous, containing: at least one polyether urethane polymer (P1) containing isocyanate groups and having a content of at least 80% by wt. 1,2-propyleneoxy units in the polyether segment, and at least one hydrophobic polymer (P2) containing isocyanate groups and being liquid at ambient temperature, obtained by reacting at least one monomeric diisocyanate and a hydrophobic diol having an OH-number ranging between 28 and 120 mg KOH/g, the polymers P1 and P2 being produced separately and said polymers P1 and P2 having a weight ratio ranging between 70/30 and 98/2.

TECHNICAL FIELD

The invention relates to moisture-curing polyurethane compositions andto the use thereof as elastic adhesives and/or sealants for constructionand industrial applications, especially for the replacement of glass inmotor vehicles.

STATE OF THE ART

Curable compositions based on polyurethanes are often used as adhesivesfor elastic bonds, for example in motor vehicle construction. Thisrequires good properties, especially with regard to storage stability,applicability, open time, curing rate, adhesion, strength, elasticity,weathering resistance and hazardous substance classification.

One-component moisture-curing systems are popular, particularly onaccount of their ease of handling. In general, these systems show goodadhesion properties. However, there are applications on specificsubstrates on which the achievement of good adhesion presentsdifficulties. One example of this is the bonding of replacement glass inmotor vehicles, where the bodywork flange as substrate has both regionswith exposed paint and regions with residues of the old adhesive thatare stuck to the paint, have not been completely removed or have beenleft as bonding substrate (“residual adhesive bead”). If the newadhesive does not adhere fully to the residual adhesive bead, theeffects may be unwanted ingress of water or wind noise, or extend as faras detachment of the pane. The moisture-curing adhesives that are nowavailable, without suitable pretreatment on the residual adhesive bead,often have only inadequate adhesion, especially when the old adhesive issignificantly aged and hence has become hard or brittle. For theimprovement of adhesion on the residual adhesive bead, it is possible touse known adhesion promoters, such as diisocyanate oligomers orderivatives thereof; however, this leads to losses in the elasticity ofthe adhesive after curing.

Hydrophobic diols are typically used in two-component polyurethanes,especially in order to improve cold flexibility or weathering stability.But they are barely used in one-component moisture-curing polyurethanes.

WO2017/103070 describes a moisture-curing polyurethane adhesive havinghigh early strength, which is heated for application. It comprises apolymer containing isocyanate groups, which is a reaction productprepared in multiple stages from a polyol mixture with dimer fattyacid-based polyol among other reactants. This reaction product has veryhigh viscosity, and its preparation is complex. On account of its poorexpressibility, it is unsuitable for adhesives that are to be applicableat room temperature, and it does not enable the desired adhesion toresidual adhesive bead.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide one-componentmoisture-curing polyurethane compositions having good adhesion onsubstrates that are difficult to bond, such as residual adhesive bead,said compositions having no disadvantages in further relevant productproperties, especially storage stability, applicability, curing rate,weathering resistance, blister formation, strength, extensibility,elasticity and hazardous substance classification.

This object is achieved by a moisture-curing composition as described inclaim 1. The composition comprises a polyether urethane polymer P1containing isocyanate groups and having a content of at least 80% byweight of 1,2-propyleneoxy units in the polyether segment and ahydrophobic polymer P2 containing isocyanate groups, based on ahydrophobic diol having an OH number in the range from 28 to 120 mgKOH/g, especially a dimer fatty acid-based polyester diol or apoly(1,2-butylene glycol). Polymers P1 and P2 are prepared separatelyfrom one another and are present in a weight ratio in the range from70/30 to 98/2. They preferably each contain a small monomericdiisocyanate content.

The composition of the invention has good processibility at roomtemperature, and has a surprisingly long open time, surprisingly goodadhesion to residual adhesive bead and particularly high weatheringresistance, without occurrence of losses in curing rate, strength,extensibility or other relevant product properties compared tocorresponding compositions without polymer P2.

Furthermore, carbon black-filled compositions of the invention havesurprisingly little tendency to exude carbon black, as a result of whichthe substrates do not stain even after prolonged use. Furthermore, thecomposition of the invention has a matt surface, which is very desirableby many users in the case of visible adhesive bonds.

It is particularly surprising that the composition of the invention hasunexpectedly good processing properties. Even with a low content ofhydrophobic polymer P2, it can be expressed from the container withparticularly low force at room temperature and at low temperatures, withunchanged good sag resistance and short threading compared tocorresponding compositions without polymer P2.

For improvement of initial strength, sag resistance and threading,moisture-curing polyurethane adhesives, especially for motor vehicleconstruction, often additionally comprise a meltable component,typically a small amount of a room temperature solid polyurethanepolymer based on a crystalline polyester polyol. However, the meltablecomponent increases the expression force for the adhesive at roomtemperature and under cold conditions, and sag resistance is highlyshear-dependent, which can lead to problems in production andapplication. Surprisingly, the composition of the invention issurprisingly easily expressible even when it additionally comprises ameltable component, with the rheological properties being significantlyless shear-dependent. More particularly, the composition of theinvention enables adhesives where the meltable component can be used ina much smaller amount or omitted entirely.

The composition of the invention enables moisture-curing elasticpolyurethane sealants and adhesives that are applicable at roomtemperature and have improved bonding properties coupled with long opentime, especially on specific substrates such as residual adhesive bead,improved application properties, especially particularly goodexpressibility, even at low temperatures, with a particularly small risein expression force between room temperature and 5° C., a matt surfaceand particularly good weathering resistance, with unchanged goodproperties in relation to storage stability, curing rate, blisterformation, strength, extensibility, elasticity and hazardous substanceclassification compared to corresponding compositions without polymerP2. The composition is thus particularly suitable as elastic adhesive inmotor vehicle construction, especially for the replacement of faulty,elastically bonded windshields to automobiles.

Further aspects of the invention are the subject of further independentclaims. Particularly preferred embodiments of the invention are thesubject of the dependent claims.

WAYS OF EXECUTING THE INVENTION

The invention provides a moisture-curing composition which is liquid orpasty at room temperature, comprising

-   -   at least one polyether urethane polymer P1 containing isocyanate        groups and having a content of at least 80% by weight of        1,2-propyleneoxy units in the polyether segment, and    -   at least one room temperature liquid, hydrophobic polymer P2        containing isocyanate groups, obtained from the reaction of at        least one monomeric diisocyanate and a hydrophobic diol having        an OH number in the range from 28 to 120 mg KOH/g,        wherein polymers P1 and P2 are prepared separately from one        another and polymer P1 and polymer P2 are present in a weight        ratio in the range from 70/30 to 98/2.

“Monomeric diisocyanate” refers to an organic compound having twoisocyanate groups separated from one another by a divalent hydrocarbylradical having 4 to 15 carbon atoms.

A “polyether urethane polymer” refers to a polymer having ether groupsas repeat units and additionally containing urethane groups.

A “dimer fatty acid-based polyester diol” refers to a polyester diolthat has been prepared proceeding from a dimer fatty acid and/or a dimerfatty alcohol.

“NCO content” refers to the content of isocyanate groups in percent byweight based on the whole polymer.

“Molecular weight” refers to the molar mass (in g/mol) of a molecule ora molecule residue. “Average molecular weight” refers to thenumber-average molecular weight (M_(n)) of a polydisperse mixture ofoligomeric or polymeric molecules or molecule residues. It is determinedby means of gel permeation chromatography (GPC) against polystyrene asstandard.

A substance or composition is referred to as “storage-stable” or“storable” when it can be stored at room temperature in a suitablecontainer over a prolonged period, typically over at least 3 months toup to 6 months or more, without any change in its application or useproperties to a degree of relevance for the use thereof as a result ofthe storage.

A composition referred to as a “one-component” composition is one inwhich all constituents of the composition are in the same container andwhich is storage-stable per se.

“Room temperature” refers to a temperature of 23° C.

All industry standards and norms mentioned in this document relate tothe versions valid at the date of first filing.

Percentages by weight (% by weight) refer to proportions by mass of aconstituent of a composition or a molecule, based on the overallcomposition or the overall molecule, unless stated otherwise. The terms“mass” and “weight” are used synonymously in the present document.

The moisture-curing composition comprises at least one polyetherurethane polymer P1 containing isocyanate groups and having a content ofat least 80% by weight of 1,2-propyleneoxy units in the polyethersegment.

The polyether urethane polymer P1 preferably comprises 80% to 100% byweight of 1,2-propyleneoxy units and 0% to 20% by weight of1,2-ethyleneoxy units in the polyether segment.

The polyether urethane polymer P1 preferably has an average NCOfunctionality in the range from 1.8 to 3.5, preferably 2 to 3.

The polyether urethane polymer P1 preferably has an NCO content in therange from 1% to 5% by weight, especially 1% to 3% by weight.

The polyether urethane polymer P1 preferably has an average molecularweight M_(n) in the range from 2 000 to 20 000 g/mol, preferably 3 000to 15 000 g/mol.

The polyether urethane polymer P1 preferably has a viscosity at 20° C.in the range from 5 to 300 Pa·s, more preferably 5 to 200 Pa·s,especially 5 to 100 Pa·s. The viscosity is determined here with acone-plate viscometer having a cone diameter 25 mm, cone angle 1°, conetip-plate distance 0.5 mm, at a shear rate of 50 s⁻¹.

The preferred polyether urethane polymers P1 enable efficientlyprocessible moisture-curing compositions having high elasticity andextensibility coupled with high strength.

The polyether urethane polymer P1 containing isocyanate groups isespecially obtained from the reaction of at least one monomericdiisocyanate and at least one suitable polyether polyol. The reaction ispreferably conducted with exclusion of moisture at a temperature in therange from 20 to 160° C., especially 40 to 140° C., optionally in thepresence of suitable catalysts.

The NCO/OH ratio is preferably in the range from 1.3/1 to 10/1. Themonomeric diisocyanate remaining in the reaction mixture after thereaction of the OH groups can be removed, especially by means ofdistillation.

If excess monomeric diisocyanate is removed by means of distillation,the NCO/OH ratio in the reaction is preferably in the range from 3/1 to10/1, especially 4/1 to 7/1, and the resultant polyether urethanepolymer containing isocyanate groups, after the distillation, preferablycontains not more than 0.5% by weight, more preferably not more than0.3% by weight, of monomeric diisocyanate.

If no excess monomeric diisocyanate is removed from the polyetherurethane polymer, the NCO/OH ratio in the reaction is preferably in therange from 1.3/1 to 2.5/1. Such a polyether urethane polymer especiallycontains not more than 3% by weight, preferably not more than 2% byweight, of monomeric diisocyanate.

Suitable monomeric diisocyanates for the preparation of the polyetherurethane polymer P1 are commercially available aromatic, aliphatic orcycloaliphatic diisocyanates, especially diphenylmethane4,4′-diisocyanate, optionally with fractions of diphenylmethane 2,4′-and/or 2,2′-diisocyanate (MDI), tolylene 2,4-diisocyanate or mixturesthereof with tolylene 2,6-diisocyanate (TDI), phenylene 1,4-diisocyanate(PDI), naphthalene 1,5-diisocyanate (NDI), hexane 1,6-diisocyanate(HDI), 2,2(4),4-trimethylhexamethylene 1,6-diisocyanate (TMDI),cyclohexane 1,3- or 1,4-diisocyanate,1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophoronediisocyanate or IPDI), perhydro(diphenylmethane 2,4′- or4,4′-diisocyanate) (HMDI), 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane,m- or p-xylylene diisocyanate (XDI), or mixtures thereof.

Among these, preference is given to MDI, TDI, HDI or IPDI. Particularpreference is given to IPDI or MDI.

Most preferred is MDI, especially diphenylmethane 4,4′-diisocyanate(4,4′-MDI). This 4,4′-MDI is especially of a quality that contains onlysmall fractions of diphenylmethane 2,4′- and/or 2,2′-diisocyanate and issolid at room temperature.

The isocyanate groups of the polyether urethane polymer P1 are thuspreferably derived from diphenylmethane 4,4′-diisocyanate. Such apolymer cures particularly rapidly and enables particularly highstrengths.

Suitable polyether polyols for the preparation of the polyether urethanepolymer P1 are polyether polyols having at least 80% by weight of1,2-propyleneoxy units in the polyether segment, especiallypolyoxypropylene diols or polyoxypropylene triols, or what are calledethylene oxide-terminated (EO-capped or EO-tipped) polyoxypropylenediols or triols. The latter are polyoxyethylene/polyoxypropylenecopolyols which are obtained especially by further alkoxylatingpolyoxypropylene diols or triols with ethylene oxide on conclusion ofthe propoxylation reaction, with the result that they have primaryhydroxyl groups.

Preference is given to polyether polyols having an OH number in therange from 6 to 280 mg KOH/g, especially 7.5 to 112 mg KOH/g.

Preference is given to polyether polyols having an average molecularweight M_(n) in the range from 400 to 20 000 g/mol, more preferably 1000to 15 000 g/mol, especially 2000 to 10 000 g/mol.

Preference is given to polyether polyols having an average OHfunctionality in the range from 1.6 to 3.

In the preparation of the polyether urethane polymer P1 containingisocyanate groups, it is also possible to include proportions of di- orpolyfunctional alcohols.

More preferably, the polyether urethane polymer P1 is obtained from thereaction of at least one monomeric diisocyanate and at least oneoptionally ethylene oxide-terminated polyoxypropylene diol or triolhaving an OH number in the range from 7.5 to 112 mg KOH/g, especially 11to 58 mg KOH/g.

In a preferred embodiment of the invention, the polyether urethanepolymer P1 containing isocyanate groups contains only a small content ofmonomeric diisocyanates. It preferably contains not more than 0.5% byweight, more preferably not more than 0.3% by weight, especially notmore than 0.2% by weight, of monomeric diisocyanates. Such a polyetherurethane polymer P1 enables compositions having a particularlyattractive hazardous substance classification.

A preferred separation method for the removal of monomeric diisocyanateis a distillative method, especially thin-film distillation orshort-path distillation, preferably with application of reducedpressure.

Particular preference is given to a multistage method in which themonomeric diisocyanate is removed in a short-path evaporator with ajacket temperature in the range from 120 to 200° C. and a pressure of0.001 to 0.5 mbar.

In the case of 4,4′-MDI, which is preferred as monomeric diisocyanate,distillative removal is particularly demanding. It has to be ensured,for example, that the condensate does not solidify and block the system.Preference is given to operating at a jacket temperature in the rangefrom 160 to 200° C. at 0.001 to 0.5 mbar, and condensing the monomerremoved at a temperature in the range from 40 to 60° C.

Preference is given to reacting the monomeric diisocyanate with thepolyether polyol and subsequently removing the majority of the monomericdiisocyanate remaining in the reaction mixture without the use ofsolvents or entraining agents.

Preference is given to subsequently reusing the monomeric diisocyanateremoved after the reaction, i.e. using it again for the preparation ofpolymer containing isocyanate groups.

Particular preference is given to a polyether urethane polymer P1 havingan NCO content in the range from 1% to 2.5% by weight, especially 1.3%to 2.1% by weight, and a monomeric diisocyanate content of not more than0.3% by weight, which is obtained from the reaction of at least onemonomeric diisocyanate and a polyether triol having an average OHfunctionality in the range from 2.2 to 3 and an OH number in the rangefrom 20 to 42 mg KOH/g in an NCO/OH ratio of at least 3/1 and subsequentremoval of a majority of the monomeric diisocyanates by means of asuitable separation method. A preferred monomeric diisocyanate is IPDIor 4,4′-MDI, especially 4,4′-MDI.

Particular preference is further given to a linear polyether urethanepolymer P1 having an NCO content in the range from 1% to 2.5% by weight,especially 1.3% to 2.1% by weight, and a monomeric diisocyanate contentof not more than 0.3% by weight, obtained from the reaction of at leastone monomeric diisocyanate with a polyether diol having an OH number inthe range from 13 to 38 mg KOH/g, especially 22 to 32 mg KOH/g, in anNCO/OH ratio of at least 3/1 and subsequent removal of a majority of themonomeric diisocyanates by means of a suitable separation method. Apreferred monomeric diisocyanate is IPDI or 4,4′-MDI, especially4,4′-MDI.

Particular preference is further given to a mixture of these twoparticularly preferred polyether urethane polymers as polyether urethanepolymer P1.

The moisture-curing composition preferably contains 15% to 80% byweight, especially 20% to 60% by weight, of polyether urethane polymerP1.

The moisture-curing composition further comprises at least one roomtemperature liquid, hydrophobic polymer P2 containing isocyanate groups,obtained from the reaction of at least one monomeric diisocyanate and ahydrophobic diol.

The polymer P2 preferably has a viscosity at 20° C. of not more than1000 Pa·s, especially not more than 500 Pa·s. The viscosity at 20° C. ispreferably in the range from 10 to 1000 Pa·s, especially 10 to 500 Pa·s.The viscosity is determined here with a cone-plate viscometer having acone diameter 25 mm, cone angle 1°, cone tip-plate distance 0.5 mm, at ashear rate of 50 s⁻¹.

The polymer P2 preferably has an NCO content in the range from 1.5% to6% by weight, more preferably 1.8% to 5% by weight, especiallypreferably 2% to 4% by weight, in particular 2.2% to 3.4% by weight.This enables an attractive combination of good expressibility, goodadhesion properties and high strength.

The hydrophobic diol is preferably selected from the group consisting ofdimer fatty acid-based polyester diols and poly(1,2-butylene glycol).These hydrophobic diols enable moisture-curing compositions havingparticularly good properties in relation to processibility,extensibility, elasticity, strength and adhesion to residual adhesivebead.

The hydrophobic diol has an OH number in the range from 28 to 120 mgKOH/g. Such diols have an average molecular weight M_(n) in the rangefrom 950 to 4000 g/mol. They have a largely linear structure and anaverage OH functionality of about 2.

The hydrophobic diol preferably has an OH number in the range from 34 to120 mg KOH/g, especially 52 to 60 mg KOH/g. Such a diol has an averagemolecular weight M_(n) in the range from 950 to 3300 g/mol, especially1900 to 2200 g/mol. It enables a particularly attractive combination ofgood expressibility, good adhesion properties and high strength.

In a preferred embodiment of the invention, the hydrophobic diol is adimer fatty acid-based polyester diol. It is preferably amorphous. Sucha hydrophobic diol enables compositions having particularly goodprocessibility in relation to threading and particularly good hydrolysisand weathering stability, especially also of carbon black-filledcompositions, as a result of which they have significantly less of atendency to exude carbon black. It additionally enables a markedly mattsurface.

Suitable dimer fatty acid-based polyester diols are especially obtainedfrom the esterification of at least one dimer fatty acid and/or at leastone dimer fatty alcohol with a diol, for example diethylene glycol orbutanediol, and/or a dicarboxylic acid, for example adipic acid, at sucha stoichiometry that the product is amorphous and is liquid at roomtemperature and has an OH number in the range from 28 to 120 mg KOH/g.

The dimer fatty acid-based polyester diol preferably contains a contentof carbon atoms from renewable sources according to ASTM D6866 based onthe total carbon content in the range from 50% to 100%, preferably 60%to 95%, especially 70% to 90%. Such a polyester diol is amorphous andhydrophobic, and enables polymers P2 having particularly goodcompatibility with the polyether urethane polymer P1.

Especially suitable are commercially available amorphous dimer fattyacid-based polyester diols, especially the following grades obtainableunder the Priplast® trade name: Priplast® 1837, 1838, 3187, 3196, 3197,3199 or 3238 (from Croda). Among these, preference is given to Priplast®1838.

In a further preferred embodiment of the invention, the hydrophobic diolis a poly(1,2-butylene glycol). This is obtained from the polymerizationof 1,2-butylene oxide. The starter used for this purpose is typicallywater or a small diol such as ethylene glycol or butane-1,2-diol. Itenables polymers P2 having particularly low viscosity and henceparticular ease of handling, and compositions having particularly rapidcuring.

Especially suitable are commercially available grades, especiallyVorapel® D3201 (from Dow).

Suitable monomeric diisocyanates are the commercially availablearomatic, aliphatic or cycloaliphatic diisocyanates already mentioned.

The monomeric diisocyanate used for the reaction is preferablydiphenylmethane 4,4′-diisocyanate (4,4′-MDI), diphenylmethane2,4′-diisocyanate (2,4′-MDI), tolylene 2,4-diisocyanate or mixturesthereof with tolylene 2,6-diisocyanate (TDI),1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI) orhexane 1,6-diisocyanate (HDI). These diisocyanates are easily obtainableand inexpensive, and enable good mechanical strengths. It is alsopossible to use a combination of two or more of these monomericdiisocyanates.

A particularly preferred monomeric diisocyanate is IPDI. Such a polymerP2 is particularly suitable in moisture-curing compositions havingparticularly high light stability.

Most preferred as monomeric diisocyanate is 4,4′-MDI. This 4,4′-MDI isespecially of a quality that contains only small fractions ofdiphenylmethane 2,4′- and/or 2,2′-diisocyanate and is solid at roomtemperature. Such a polymer P2 enables particularly rapid curing andhigh strengths.

The reaction of at least one monomeric diisocyanate and the hydrophobicdiol for preparation of the polymer P2 is preferably conducted withexclusion of moisture at a temperature in the range from 20 to 160° C.,especially 40 to 140° C., optionally in the presence of suitablecatalysts.

The NCO/OH ratio is preferably in the range from 1.3/1 to 10/1. Themonomeric diisocyanate remaining in the reaction mixture after thereaction of the OH groups can be removed, especially by means ofdistillation. If excess monomeric diisocyanate is removed by means ofdistillation, the NCO/OH ratio in the reaction is preferably in therange from 3/1 to 10/1, especially 4/1 to 7/1, and the resultant polymercontaining isocyanate groups, after the distillation, preferablycontains not more than 0.5% by weight, more preferably not more than0.3% by weight, of monomeric diisocyanate.

If no excess monomeric diisocyanate is removed from the polymer, theNCO/OH ratio in the reaction is preferably in the range from 1.3/1 to2.5/1. Such a polymer especially contains not more than 3% by weight,preferably not more than 2% by weight, of monomeric diisocyanate.

Polymer P2 preferably has a monomeric diisocyanate content of not morethan 0.5% by weight and is obtained from the reaction of at least onemonomeric diisocyanate and the hydrophobic diol in an NCO/OH ratio of atleast 3/1, followed by removal of a majority of the monomericdiisocyanate by means of a suitable separation method.

Such a polymer P2 is particularly low viscosity, which makes it easierto handle, and it is particularly suitable for use in compositionshaving less than 0.1° A by weight of monomeric diisocyanates; these aresafe to handle even without special safety precautions and can be soldin many countries without hazardous substance classification.

The NCO/OH ratio in the reaction is preferably in the range from 3/1 to10/1, more preferably 3/1 to 8/1, especially 4/1 to 7/1.

The monomeric diisocyanate content is preferably not more than 0.3% byweight, especially not more than 0.2% by weight.

A preferred separation method for the removal of monomeric diisocyanateis a distillative method, especially thin-film distillation orshort-path distillation, preferably with application of reducedpressure.

Particular preference is given to a multistage method in which themonomeric diisocyanate is removed in a short-path evaporator with ajacket temperature in the range from 120 to 200° C. and a pressure of0.001 to 0.5 mbar.

Preference is given to reacting the monomeric diisocyanate with thehydrophobic diol and subsequently removing the majority of the monomericdiisocyanate remaining in the reaction mixture without the use ofsolvents or entraining agents.

Preference is given to subsequently reusing the monomeric diisocyanateremoved after the reaction, i.e. using it again for the preparation ofpolymer containing isocyanate groups.

The moisture-curing composition of the invention preferably contains 1%to 15% by weight, preferably 1% to 10% by weight, especially 2% to 8% byweight, of polymer P2.

The polyether urethane polymer P1 and polymer P2 are prepared separatelyfrom one another. They are thus mixed with one another only afterpreparation, especially only in the moisture-curing composition of theinvention.

The polyether urethane polymer P1 and polymer P2 are present in themoisture-curing composition of the invention in a weight ratio in therange from 70/30 to 98/2, preferably 75/25 to 97/3, especially 80/20 to95/5. Such a composition has particularly good processing properties,rapid curing and high extensibility coupled with high strength and goodbonding properties.

The moisture-curing composition preferably comprises, aside from thepolymers P1 and P2, only a small amount of further polymers containingisocyanate groups, especially not more than 20 parts by weight,preferably not more than 15 parts by weight, especially not more than 10parts by weight, of further polymers containing isocyanate groups, basedon 100 parts by weight of the sum total of polymers P1 and P2.

The moisture-curing composition preferably additionally comprises atleast one further constituent selected from meltable components, blockedamines, fillers, plasticizers, diisocyanate oligomers, catalysts andstabilizers.

In one embodiment of the invention, the moisture-curing compositionpreferably additionally comprises at least one meltable component.

A suitable meltable component is especially a room temperature solidpolyester urethane polymer containing isocyanate groups which isobtained from the reaction of at least one monomeric diisocyanate,especially 4,4′-MDI, and at least one crystalline polyester diol orpolycarbonate diol.

Suitable polyester diols are especially OH-functional polyesters ofadipic acid or sebacic acid or dodecanedicarboxylic acid withbutane-1,4-diol or hexane-1,6-diol.

Suitable polycarbonate diols are especially OH-functional polycarbonatesof hexane-1,6-diol.

Such a polymer is typically solid at room temperature and has at leastpartially crystalline character.

Such a meltable component is firstly suitable for adhesives that areapplied in the heated state, for example at a temperature of about 60°C., and very quickly after application have a high initial strength,such that the bonded parts are self-supporting and need not be fixed.The meltable component here is in molten form in the heated adhesive onapplication, and crystallizes as the applied adhesive cools down. Inaddition, such a meltable component is suitable for adhesives that areapplied at ambient temperature, where the meltable component is incrystallized form and results in an elevated sag resistance. However,the meltable component is difficult to handle, and the sag resistanceachieved therewith is highly shear-dependent, which can lead to problemsin production and application. Moreover, the meltable component makes itdifficult to express the adhesive at room temperature and at coldambient or adhesive temperatures.

Polymer P2 enables compositions having a certain proportion of meltablecomponent and having better expressibility at room temperature and undercold conditions.

In addition, polymer P2 enables compositions having very good sagresistance, in which the meltable component is used in a much smalleramount, or which are entirely free of meltable component.

In a further embodiment of the invention, the moisture-curingcomposition preferably additionally comprises at least one blockedamine.

A suitable blocked amine preferably has at least one aldimino group oroxazolidino group. On contact with moisture, it is hydrolyzed withrelease of the amino group and reacts with available isocyanate groups,and can promote rapid, blister-free curing, a particularly nontackysurface and/or particularly good mechanical properties.

Preferred oxazolidines are monooxazolidines or bisoxazolidines,especially those derived from isobutyraldehyde, benzaldehyde orsubstituted benzaldehyde, especially benzaldehyde substituted in thepara position by an optionally branched alkyl group having 10 to 14carbon atoms.

Particular preference is given to monooxazolidines derived fromN-alkylethanolamines such as N-n-butylethanolamine, or bisoxazolidinesfrom the reaction of OH-functional monooxazolidines derived fromdiethanolamine with diisocyanates, especially hexane 1,6-diisocyanate.

Suitable aldimines are especially di- or trialdimines from the reactionof commercial primary di- or triamines with non-enolizable aldehydes.These are aldehydes that do not have a hydrogen atom in the alphaposition to the carbon atom of the aldehyde group.

Preferred blocked amines are selected from aldimines of the formula (I)and (II)

wheren is 2 or 3,A is an n-valent hydrocarbyl radical optionally including ether oxygenand having a molecular weight in the range from 28 to 6000 g/mol,R¹ and R² are each independently a monovalent hydrocarbyl radical having1 to 12 carbon atoms, or together are a divalent hydrocarbyl radicalhaving 4 to 12 carbon atoms which is part of an optionally substitutedcarbocyclic ring having 5 to 8, preferably 6, carbon atoms,R³ is a hydrogen radical or a linear or branched alkyl, arylalkyl oralkoxycarbonyl radical having 1 to 12 carbon atoms,R⁴ is a hydrogen radical or a monovalent hydrocarbyl radical having 1 to20 carbon atoms, andR⁵ is an alkyl or alkoxy radical having 6 to 20 carbon atoms.

A is preferably an aliphatic, cycloaliphatic or arylaliphatic radical,especially having a molecular weight in the range from 28 to 500 g/mol,especially a radical selected from the group consisting of 1,6-hexylene,(1,5,5-trimethylcyclohexan-1-yl)methane-1,3,4(2)-methyl-1,3-cyclohexylene,1,3-cyclohexylenebis(methylene), 1,4-cyclohexylenebis(methylene),1,3-phenylenebis(methylene), 1,2-cyclohexylene, 1,3-cyclohexylene,1,4-cyclohexylene, methylenebis(2-methylcyclohexan-4-yl),(bicyclo[2.2.1]heptane-2,5(2,6)-diyl)dimethylene,(tricyclo[5.2.1.0^(2,6)]decan-3(4),8(9)-diyl)dimethylene,α,ω-polyoxypropylene having an average molecular weight M_(n) in therange from 170 to 500 g/mol and trimethylolpropane- or glycerol-startedtris(ω-polyoxypropylene) having an average molecular weight M_(n) in therange from 330 to 500 g/mol.

Preferably, R¹ and R² are each methyl.

Preferably, R³ is a hydrogen radical.

Preferably, R⁴ is methyl or undecyl.

Preferably, R⁵ is an optionally branched alkyl radical in the paraposition having 10 to 14 carbon atoms.

Particularly preferred blocked amines are selected from the groupconsisting ofN,N′-bis(2,2-dimethyl-3-lauroyloxypropylidene)hexylene-1,6-diamine,N,N′-bis(2,2-dimethyl-3-acetoxypropylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine,N,N′-bis(2,2-dimethyl-3-lauroyloxypropylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine,N,N′-bis(4-C₁₀₋₁₄-alkylbenzylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine,N,N′-bis(2,2-dimethyl-3-acetoxypropylidene)polyoxypropylenediaminehaving an average molecular weight M_(n) in the range from 450 to 880g/mol,N,N′-bis(2,2-dimethyl-3-lauroyloxypropylidene)polyoxypropylenediaminehaving an average molecular weight M_(n) in the range from 750 to 1050g/mol, N,N′-bis(4-C₁₀₋₁₄-alkylbenzylidene)polyoxypropylenediamine havingan average molecular weight M_(n) in the range from 680 to 1100 g/mol,N,N′,N″-tris(2,2-dimethyl-3-acetoxypropylidene)polyoxypropylenetriaminehaving an average molecular weight M_(n) in the range from 730 to 880g/mol,N,N′,N″-tris(2,2-dimethyl-3-lauroyloxypropylidene)polyoxypropylenetriaminehaving an average molecular weight M_(n) in the range from 1150 to 1300g/mol andN,N′,N″-tris(4-C₁₀₋₁₄-alkylbenzylidene)polyoxypropylenetriamine havingan average molecular weight M_(n) in the range from 1000 to 1350 g/mol.

Suitable fillers are especially ground or precipitated calciumcarbonates, optionally coated with fatty acids, especially stearates,barytes, quartz flours, quartz sands, dolomites, wollastonites, calcinedkaolins, sheet silicates, such as mica or talc, zeolites, aluminumhydroxides, magnesium hydroxides, silicas, including finely dividedsilicas from pyrolysis processes, cements, gypsums, fly ashes,industrially produced carbon blacks, graphite, metal powders, forexample of aluminum, copper, iron, silver or steel, PVC powders orlightweight fillers such as hollow glass beads or gas-filled plasticspheres (microspheres), especially the types obtainable under theExpancel® brand name (from Akzo Nobel).

Preference is given to calcium carbonates that have optionally beencoated with fatty acids, especially stearates, calcined kaolins, finelydivided silicas or industrially produced carbon blacks.

Suitable plasticizers are especially carboxylic esters, such asphthalates, especially diisononyl phthalate (DINP), diisodecyl phthalate(DIDP) or di(2-propylheptyl)phthalate (DPHP), hydrogenated phthalates orcyclohexane-1,2-dicarboxylates, especially hydrogenated diisononylphthalate or diisononyl cyclohexane-1,2-dicarboxylate (DINCH),terephthalates, especially bis(2-ethylhexyl) terephthalate (DOTP) ordiisononyl terephthalate (DINT), hydrogenated terephthalates orcyclohexane-1,4-dicarboxylates, especially hydrogenatedbis(2-ethylhexyl) terephthalate or bis(2-ethylhexyl)cyclohexane-1,4-dicarboxylate, or hydrogenated diisononyl terephthalateor diisononyl cyclohexane-1,4-dicarboxylate, isophthalates,trimellitates, adipates, especially dioctyl adipate, azelates,sebacates, benzoates, glycol ethers, glycol esters, plasticizers havingpolyether structure, especially polypropylene oxide monools, diols ortriols having blocked hydroxyl groups, especially in the form of acetategroups, organic phosphoric or sulfonic esters, polybutenes,polyisobutenes or plasticizers derived from natural fats or oils,especially epoxidized soybean or linseed oil.

Preferred plasticizers are phthalates or plasticizers having polyetherstructure.

Suitable diisocyanate oligomers are especially HDI biurets such asDesmodur® N 100 or N 3200 (from Covestro AG), Tolonate® HDB or HDB-LV(from Vencorex) or Duranate® 24A-100 (from Asahi Kasei); HDIisocyanurates such as Desmodur® N 3300, N 3600 or N 3790 BA (all fromCovestro), Tolonate® HDT, HDT-LV or HDT-LV2 (from Vencorex), Duranate®TPA-100 or THA-100 (from Asahi Kasei) or Coronate® HX (from TosohCorp.); HDI uretdiones such as Desmodur® N 3400 (from Covestro); HDIiminooxadiazinediones such as Desmodur® XP 2410 (from Covestro); HDIallophanates such as Desmodur® VP LS 2102 (from Covestro); IPDIisocyanurates, for example in solution as Desmodur® Z 4470 (fromCovestro) or in solid form as Vestanat® T1890/100 (from EvonikIndustries); TDI oligomers such as Desmodur® IL (from Covestro); ormixed isocyanurates based on TDI/HDI, such as Desmodur® HL (fromCovestro).

Suitable catalysts are catalysts for the acceleration of the reaction ofisocyanate groups, especially organotin(IV) compounds such as, inparticular, dibutyltin diacetate, dibutyltin dilaurate, dibutyltindichloride, dibutyltin diacetylacetonate, dimethyltin dilaurate,dioctyltin diacetate, dioctyltin dilaurate or dioctyltindiacetylacetonate, complexes of bismuth(III) or zirconium(IV),especially with ligands selected from alkoxides, carboxylates,1,3-diketonates, oxinate, 1,3-ketoesterates and 1,3-ketoamidates, orcompounds containing tertiary amino groups, such as especially2,2′-dimorpholinodiethyl ether (DMDEE).

If the moisture-curing composition contains blocked amines, suitablecatalysts are also catalysts for the hydrolysis of the blocked aminogroups, especially organic acids, especially carboxylic acids such as2-ethylhexanoic acid, lauric acid, stearic acid, isostearic acid, oleicacid, neodecanoic acid, benzoic acid, salicylic acid or 2-nitrobenzoicacid, organic carboxylic anhydrides such as phthalic anhydride,hexahydrophthalic anhydride or methylhexahydrophthalic anhydride, silylesters of carboxylic acids, organic sulfonic acids such asmethanesulfonic acid, p-toluenesulfonic acid or 4-dodecylbenzenesulfonicacid, sulfonic esters, other organic or inorganic acids, or mixtures ofthe aforementioned acids and acid esters. Particular preference is givento carboxylic acids, especially aromatic carboxylic acids, such asbenzoic acid, 2-nitrobenzoic acid or especially salicylic acid.

Also especially suitable are combinations of different catalysts.

Suitable stabilizers are especially stabilizers against oxidation, heat,light or UV radiation, especially titanium dioxides, iron oxides, zincoxides, benzophenones, benzotriazoles, compounds having2,6-di-tert-butylphenol groups, as known, for example, under theIrganox® trade name (from BASF), compounds having2,2,6,6-tetramethylpiperidine groups, called HALS (hindered amine lightstabilizers), as known, for example, under the Tinuvin® trade name (fromBASF), or phosphorus-containing compounds as known, for example, underthe Irgafos® trade name (from BASF).

The moisture-curing composition may contain further additions,especially

-   -   inorganic or organic pigments, especially titanium dioxide,        chromium oxides or iron oxides;    -   fibers, especially glass fibers, carbon fibers, metal fibers,        ceramic fibers, polymer fibers, such as polyamide fibers or        polyethylene fibers, or natural fibers, such as wool, cellulose,        hemp or sisal;    -   nanofillers such as graphene or carbon nanotubes;    -   dyes;    -   desiccants, especially molecular sieve powder, calcium oxide,        highly reactive isocyanates such as p-tosyl isocyanate,        monooxazolidines such as Incozol® 2 (from Incorez) or        orthoformic esters;    -   adhesion promoters, especially organoalkoxysilanes, especially        epoxysilanes, such as especially        3-glycidoxypropyltrimethoxysilane or        3-glycidoxypropyltriethoxysilane, (meth)acrylosilanes,        anhydridosilanes, carbamatosilanes, alkylsilanes or        iminosilanes, or oligomeric forms of these silanes, or        titanates;    -   further catalysts which accelerate the reaction of the        isocyanate groups;    -   rheology modifiers, especially thickeners, especially sheet        silicates, such as bentonites, derivatives of castor oil,        hydrogenated castor oil, polyam ides, polyamide waxes,        polyurethanes, urea compounds, fumed silicas, cellulose ethers        or hydrophobically modified polyoxyethylenes;    -   solvents, especially acetone, methyl acetate, tert-butyl        acetate, 1-methoxy-2-propyl acetate, ethyl 3-ethoxypropionate,        diisopropyl ether, diethylene glycol diethyl ether, ethylene        glycol diethyl ether, ethylene glycol monobutyl ether, ethylene        glycol mono-2-ethylhexyl ether, acetals such as propylal,        butylal, 2-ethylhexylal, dioxolane, glycerol formal or        2,5,7,10-tetraoxaundecane (TOU), toluene, xylene, heptane,        octane, naphtha, white spirit, petroleum ether or gasoline,        especially Solvesso™ grades (from Exxon), and propylene        carbonate, dimethyl carbonate, butyrolactone,        N-methylpyrrolidone, N-ethylpyrrolidone,        p-chlorobenzotrifluoride or benzotrifluoride;    -   natural resins, fats or oils, such as rosin, shellac, linseed        oil, castor oil or soybean oil;    -   nonreactive polymers, especially homo- or copolymers of        unsaturated monomers, especially from the group comprising        ethylene, propylene, butylene, isobutylene, isoprene, vinyl        acetate or alkyl (meth)acrylates, especially polyethylenes (PE),        polypropylenes (PP), polyisobutylenes, ethylene/vinyl acetate        copolymers (EVA) or atactic poly-a-olefins (APAO);    -   flame-retardant substances, especially the aluminum hydroxide or        magnesium hydroxide fillers already mentioned, and also        especially organic phosphoric esters, such as especially        triethyl phosphate, tricresyl phosphate, triphenyl phosphate,        diphenyl cresyl phosphate, isodecyl diphenyl phosphate,        tris(1,3-dichloro-2-propyl) phosphate, tris(2-chloroethyl)        phosphate, tris(2-ethylhexyl) phosphate, tris(chloroisopropyl)        phosphate, tris(chloropropyl) phosphate, isopropylated triphenyl        phosphate, mono-, bis-or tris(isopropylphenyl) phosphates of        different degrees of isopropylation, resorcinol        bis(diphenylphosphate), bisphenol A bis(diphenylphosphate) or        ammonium polyphosphates;    -   additives, especially wetting agents, leveling agents,        defoamers, deaerating agents or biocides;        or further substances customarily used in moisture-curing        polyurethane compositions.

It may be advisable to chemically or physically dry certain substancesbefore mixing them into the composition.

Preferably, the composition of the invention contains little solvent. Itespecially contains less than 5% by weight, preferably less than 2.5% byweight, of solvent. Most preferably, the composition of the invention isessentially free of solvents.

The moisture-curing composition preferably contains

-   -   20% to 60% by weight of polyether urethane polymers P1,    -   0.5% to 10% by weight of polymer P2,    -   0% to 5% by weight of meltable component,    -   20% to 60% by weight of fillers,    -   0% to 35% by weight of plasticizers,        and optionally further constituents, especially blocked amines,        diisocyanate oligomers, catalysts or stabilizers.

In a preferred embodiment of the invention, the moisture-curingcomposition comprises carbon black, especially at least one industriallyproduced carbon black, especially in an amount in the range from 5% to40% by weight, preferably 10% to 30% by weight. Such a composition,owing to its high sag resistance, strength and stability, isparticularly suitable for bonding of glass panes, and has a particularlylow tendency to exude carbon black due to the hydrophobic polymer P2.

The moisture-curing composition preferably contains less than 0.1° A byweight of monomeric diisocyanates. Such a composition can be transportedand sold in many countries without hazardous substance classification.

The moisture-curing composition is especially produced with exclusion ofmoisture and stored at ambient temperature in moisture-tight containers.A suitable moisture-tight container especially consists of an optionallycoated metal and/or plastic, and is especially a drum, a transport box,a hobbock, a bucket, a canister, a can, a bag, a tubular bag, acartridge or a tube.

The moisture-curing composition is preferably a one-componentcomposition. Given suitable packaging and storage, it is storage-stable,typically over several months, up to one year or longer.

The moisture-curing composition begins to cure during and afterapplication under the influence of moisture or water. For accelerationof the curing, an accelerator component containing water and optionallya catalyst and/or a curing agent can be mixed into the composition onapplication, or the composition, after application thereof, can becontacted with such an accelerator component.

In the course of curing, the isocyanate groups react with one anotherunder the influence of moisture. If the moisture-curing compositioncontains a blocked amine, the isocyanate groups additionally react withthe blocked amino groups as they are hydrolyzed. The totality of thesereactions of isocyanate groups that lead to the curing of thecomposition is also referred to as crosslinking. This results in thecured composition.

The moisture required for the curing of the composition preferably getsinto the composition through diffusion from the air (atmosphericmoisture). In the process, a solid layer of cured composition (“skin”)is formed on the surfaces of the composition which come into contactwith air. The curing continues in the direction of diffusion from theoutside inward, the skin becoming increasingly thick and ultimatelyencompassing the entire composition applied. The moisture can also getinto the composition additionally or entirely from one or moresubstrate(s) to which the composition has been applied and/or can comefrom an accelerator component which is mixed into the composition onapplication or is contacted therewith after application, for example bypainting or spraying.

The moisture-curing composition is preferably applied at ambienttemperature, especially in the range from about −10 to 50° C.,preferably in the range from −5 to 45° C., especially 0 to 40° C.

If desired, the moisture-curing composition can also be applied in theheated state, for example at a temperature of about 60° C.

The moisture-curing composition is preferably cured at ambienttemperature.

The moisture-curing composition has a long processing time (open time)and rapid curing.

“Open time” refers to the period of time during which the compositioncan be processed or reprocessed after application without any loss ofits ability to function. If the composition is used as adhesive, theopen time especially also refers to the period of time within which abond must have been made after application thereof in order to developsufficient adhesion. The open time has been surpassed at least when askin has formed or when there is no longer sufficient buildup ofadhesion to the substrates.

The moisture-curing composition is preferably used as elastic adhesiveand/or sealant, especially for bonding or sealing applications in theconstruction and manufacturing industry or in motor vehicleconstruction, especially for parquet bonding, assembly, bonding ofinstallable components, module bonding, pane bonding, join sealing,bodywork sealing, seam sealing or cavity sealing.

Elastic bonds in motor vehicle construction are, for example, the bondedattachment of parts such as plastic covers, trim strips, flanges,fenders, driver's cabins or other installable components to the paintedbody of a motor vehicle, or the bonding of panes into the vehicle body,said motor vehicles especially being automobiles, trucks, buses, railvehicles or ships.

Particular preference is given to use as adhesive for the glazing ofmotor vehicles, especially for the replacement of glass in motorvehicles.

The moisture-curing composition is preferably formulated such that ithas a pasty consistency with structurally viscous properties at roomtemperature. A composition of this kind is applied by means of asuitable device, for example from commercial cartridges or kegs orhobbocks, especially in the form of a bead, which may have anessentially round or triangular cross-sectional area.

Suitable substrates which can be bonded and/or sealed with themoisture-curing composition are especially

-   -   glass, glass ceramic or screenprinted ceramic-coated glass or        polycarbonate;    -   metals or alloys, such as aluminum, copper, iron, steel,        nonferrous metals, including surface-finished metals or alloys,        such as zinc-plated or chromium-plated metals;    -   coated or painted substrates, especially powder-coated metals or        alloys or painted sheet metal;    -   paints or varnishes, especially automotive topcoats;    -   cured adhesives, especially based on polyurethane,        silane-modified polymer or polysulfide, especially aged        adhesives (residual adhesive bead), or bodywork flange having        residual adhesive bead everywhere or in places;    -   plastics, such as rigid or flexible PVC, polycarbonate,        polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resins,        phenolic resins, PUR, POM, TPO, PE, PP, EPM or EPDM, in each        case untreated or surface-treated, for example by means of        plasma, corona or flames;    -   fiber-reinforced plastics, such as carbon fiber-reinforced        plastics (CFP), glass fiber-reinforced plastics (GFP) and sheet        molding compounds (SMC);    -   repair or leveling compounds based on PCC (polymer-modified        cement mortar) or ECC (epoxy resin-modified cement mortar);    -   insulation foams, especially made of EPS, XPS, PUR, PIR, rock        wool, glass wool or foamed glass;    -   concrete, mortar, cement screed, fiber cement, especially fiber        cement boards, brick, tile, gypsum, especially gypsum boards or        anhydride screed, or natural stone, such as granite or marble,        painted tiles or painted concrete, asphalt or bitumen;    -   leather, textiles, paper, wood, wood materials bonded with        resins, such as phenolic, melamine or epoxy resins,        resin/textile composites or further materials called polymer        composites.

If required, the substrates can be pretreated prior to application,especially by physical and/or chemical cleaning methods or theapplication of an activator or a primer.

It is possible to bond and/or seal two identical or two differentsubstrates.

The invention further provides a method of bonding or sealing,comprising the steps of

(i) applying the moisture-curing composition described

-   -   to a first substrate and contacting the composition with a        second substrate within the open time of the composition, or    -   to a first and to a second substrate and joining the two        substrates within the open time of the composition, or    -   between two substrates,

(ii) curing the composition by contact with moisture.

At least one of the substrates is preferably selected from the groupconsisting of glass, glass ceramic, screenprinted ceramic-coated glassor polycarbonate, metals, alloys, powder-coated metals or alloys, paintsand varnishes and cured adhesive, especially residual adhesive bead,and/or sheet metal painted with automotive topcoats.

The application and curing of the moisture-curing composition or themethod of bonding or sealing affords an article bonded or sealed withthe composition. This article may be a built structure or a partthereof, especially a built structure in civil engineering above orbelow ground, a bridge, a roof, a staircase or a façade, or it may be anindustrial good or a consumer good, especially a window, a pipe, a rotorblade of a wind turbine, a domestic appliance or a mode of transport,such as especially an automobile, a bus, a truck, a rail vehicle, aship, an aircraft or a helicopter, or an installable component thereof.

The invention thus further provides an article obtained from thedescribed method of bonding or sealing.

Particular preference is given to using the method of bonding for theelastic bonding of glass panes to motor vehicles, especially for thereplacement of glass, where good adhesion to residual adhesive bead isparticularly important.

The moisture-curing composition has advantageous properties. It hasparticularly good bonding properties coupled with long open time,especially on residual adhesive bead, particularly good applicationproperties, especially particularly good expressibility coupled withhigh sag resistance, a matt surface and particularly good weatheringresistance, coupled with unchanged good curing, strength, extensibility,elasticity and hazardous substance classification. The composition isthus particularly suitable as elastic adhesive in motor vehicleconstruction, especially for the replacement of faulty, elasticallybonded windshields to automobiles.

EXAMPLES

Working examples are adduced hereinafter, which are intended toelucidate the invention described. The invention is of course notlimited to these described working examples.

“Standard climatic conditions” (SCC) refer to a temperature of 23±1° C.and a relative air humidity of 50±5%.

Unless otherwise stated, the chemicals used were from Sigma-AldrichChemie GmbH.

Polyols Used:

-   Desmophen® 5031 BT: glycerol-started ethylene oxide-terminated    polyoxypropylene triol, OH number 28 mg KOH/g (from Covestro)-   Acclaim® 4200: polyoxypropylene diol, OH number 28 mg KOH/g (from    Covestro)-   Priplast® 1838: dimer fatty acid-based amorphous polyester diol, OH    number 56 mg KOH/g, liquid at room temperature (from Croda)    (=hydrophobic diol)-   Priplast® 1837: dimer fatty acid-based amorphous polyester diol, OH    number 110 mg KOH/g, liquid at room temperature (from Croda)    (=hydrophobic diol)-   Priplast® 3196: dimer fatty acid-based amorphous polyester diol, OH    number 37 mg KOH/g, liquid at room temperature (from Croda)    (=hydrophobic diol)-   Priplast® 3197: dimer fatty acid-based amorphous polyester diol, OH    number 56 mg KOH/g, liquid at room temperature (from Croda)    (=hydrophobic diol)-   Vorapel® D3201: poly(1,2-butylene glycol), OH number 56 mg KOH/g,    liquid at room temperature (from Dow) (=hydrophobic diol)-   Dynacoll® 7360: room temperature solid, semicrystalline polyester    diol, OH number 34 mg KOH/g (from Evonik)

Preparation of Polymers Containing Isocyanate Groups:

Viscosity was measured with a thermostated Rheotec RC30 cone-plateviscometer (cone diameter 25 mm, cone angle 1°, cone tip-plate distance0.5 mm, shear rate 50 s⁻¹).

Monomeric diisocyanate content was determined by means of HPLC(detection via photodiode array; 0.04 M sodium acetate/acetonitrile asmobile phase) after prior derivatization by means ofN-propyl-4-nitrobenzylamine.

Polymer P1-1:

725.0 g of Desmophen® 5031 BT and 275.0 g of diphenylmethane4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted by aknown method to give a polyether urethane polymer having an NCO contentof 7.6% by weight, a viscosity of 6.5 Pa·s at 20° C. and adiphenylmethane 4,4′-diisocyanate content of about 20% by weight.

Subsequently, the volatile constituents, especially a majority of thediphenylmethane 4,4′-diisocyanate, were removed by distillation in ashort-path evaporator (jacket temperature 180° C., pressure 0.1 to 0.005mbar, condensation temperature 47° C.). The polyether urethane polymerthus obtained had an NCO content of 1.7% by weight, a viscosity of 19Pa·s at 20° C. and a diphenylmethane 4,4′-diisocyanate content of 0.04%by weight.

Polymer P1-2:

727.0 g of Acclaim® 4200 and 273.0 g of diphenylmethane4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted by aknown method to give a polyether urethane polymer having an NCO contentof 7.6% by weight, a viscosity of 5.2 Pa·s at 20° C. and adiphenylmethane 4,4′-diisocyanate content of about 18% by weight.

Subsequently, the volatile constituents, especially a majority of thediphenylmethane 4,4′-diisocyanate, were removed as described for polymerP1-1. The polyether urethane polymer thus obtained had an NCO content of1.8% by weight, a viscosity of 15.2 Pa·s at 20° C. and a diphenylmethane4,4′-diisocyanate content of 0.08% by weight.

Polymer P2-1:

597.5 g of Priplast® 1838 and 402.5 g of diphenylmethane4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted at 80°C. to give a polymer having an NCO content of 11.0% by weight, aviscosity of 36 Pa·s at 20° C. and a diphenylmethane 4,4′-diisocyanatecontent of about 26% by weight.

Subsequently, the volatile constituents, especially a majority of thediphenylmethane 4,4′-diisocyanate, were removed as described for polymerP1-1. The polymer thus obtained was slightly cloudy and was of fluid,viscous consistency at room temperature. It had an NCO content of 2.8%by weight, a viscosity of 312 Pa·s at 20° C. or 11.5 Pa·s at 60° C. anda diphenylmethane 4,4′-diisocyanate content of 0.09% by weight.

Polymer P2-2:

445.0 g of Priplast® 1837 and 555.0 g of diphenylmethane4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted at 80°C. to give a polymer having an NCO content of 14.8% by weight, aviscosity of 6.5 Pa·s at 20° C. and a diphenylmethane 4,4′-diisocyanatecontent of about 35% by weight.

Subsequently, the volatile constituents, especially a majority of thediphenylmethane 4,4′-diisocyanate, were removed as described for polymerP1-1. The polymer thus obtained was slightly cloudy and was of fluid,viscous consistency at room temperature. It had an NCO content of 4.8%by weight, a viscosity of 11 Pa·s at 60° C. and a diphenylmethane4,4′-diisocyanate content of 0.06% by weight.

Polymer P2-3:

663.0 g of Priplast® 3196 and 337.0 g of diphenylmethane4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted at 80°C. to give a polymer having an NCO content of 9.4% by weight, aviscosity of 57 Pa·s at 20° C. and a diphenylmethane 4,4′-diisocyanatecontent of about 23% by weight.

Subsequently, the volatile constituents, especially a majority of thediphenylmethane 4,4′-diisocyanate, were removed as described for polymerP1-1. The polymer thus obtained was slightly cloudy and was of fluid,viscous consistency at room temperature. It had an NCO content of 2.2%by weight, a viscosity of 17 Pa·s at 60° C. and a diphenylmethane4,4′-diisocyanate content of 0.06% by weight.

Polymer P2-4:

600.0 g of Priplast® 3197 and 400.0 g of diphenylmethane4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted at 80°C. to give a polymer having an NCO content of 10.7% by weight, aviscosity of 28 Pa·s at 20° C. and a diphenylmethane 4,4′-diisocyanatecontent of about 25% by weight. Subsequently, the volatile constituents,especially a majority of the diphenylmethane 4,4′-diisocyanate, wereremoved as described for polymer P1-1. The polymer thus obtained wasslightly cloudy and was of fluid, viscous consistency at roomtemperature. It had an NCO content of 2.8% by weight, a viscosity of 16Pa·s at 60° C. and a diphenylmethane 4,4′-diisocyanate content of 0.08%by weight.

Polymer P2-5:

601.1 g of Vorapel° D3201 and 398.9 g of diphenylmethane4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted at 80°C. to give a polymer having an NCO content of 10.7% by weight, aviscosity of 3.5 Pa·s at 20° C. and a diphenylmethane 4,4′-diisocyanatecontent of about 24% by weight. Subsequently, the volatile constituents,especially a majority of the diphenylmethane 4,4′-diisocyanate, wereremoved as described for polymer P1-1. The polymer thus obtained had anNCO content of 3.0% by weight, a viscosity of 26 Pa·s at 20° C. and adiphenylmethane 4,4′-diisocyanate content of 0.06% by weight.

Polymer M:

1000 g of Dynacoll® 7360 and 142 g of diphenylmethane 4,4′-diisocyanate(Desmodur® 44 MC L, from Covestro) were reacted at 80° C. to give a roomtemperature solid polymer having an NCO content of 2.0% by weight and adiphenylmethane 4,4′-diisocyanate content of 2.3% by weight.

Polymers P1-1 and P1-2 are polyether urethane polymers P1. Polymers P2-1to P2-5 are hydrophobic polymers P2. Polymer M is a room temperaturesolid polymer that was used as meltable component.

Moisture-Curing Compositions: Compositions Z1 to Z6:

For each composition, the ingredients specified in table 1 were wellmixed in the amounts specified (in parts by weight) by means of aplanetary mixer under reduced pressure and with exclusion of moisture,and the composition was dispensed into a tubular bag with an airtightseal and stored at room temperature.

For rapid curing, a water-containing accelerator component was added tothe composition on application. For this purpose, the composition wasapplied from a PowerCure dispenser (available from Sika Schweiz AG),with metered addition of 2% by weight of a water-containing paste intothe composition on expression and mixing-in by means of a dynamic mixer.

Adhesion to residual adhesive bead was determined on a cured and agedadhesive layer. For this purpose, a commercially available polyurethaneadhesive for bonding of glass panes (Sikaflex®-250 SV-3, from SikaAutomotive Hamburg GmbH) was applied in the form of a triangular bead ofwidth about 8 mm and height about 10 mm to a glass body, covered with asilicone-coated release paper, pressed to a layer thickness of about 5mm and cured under standard climatic conditions for 7 days, the releasepaper was removed and the compressed adhesive bead was aged at 80° C.for 14 days.

Subsequently, the cured and aged adhesive bead was cut away from theglass body down to a layer thickness of about 1 mm.

Thereafter, under standard climatic conditions, the acceleratedcomposition was applied from the PowerCure dispenser in the form of atriangular bead of width about 8 mm and height about 10 mm to strips ofsilicone-coated release paper. After the wait time specified in eachcase in table 1, the triangular beads applied to the release paper wereupturned and placed onto the residual adhesive bead remaining on theglass body in such a way that the release paper was on top and thecomposition was in contact with the residual adhesive bead.Subsequently, the composition was pressed to a layer thickness of about5 mm and cured under standard climatic conditions for 7 d, then therelease paper was removed and the adhesion of the cured composition onthe residual adhesive bead was tested by making an incision into thecured composition at the narrow end just above the bond surface, holdingthe incised end of the composition with rounded tweezers and attemptingto pull the composition away from the substrate (=residual adhesivebead). Then the composition was incised again down to the substrate, thepart that had been cut away was rolled up with the rounded tweezers andan attempt was again made to pull the composition away from thesubstrate. In this way, the composition was cut away from the substrateby puffing. Subsequently, bonding was assessed with reference to thefailure profile using the following scale;

-   “very good” represents more than 95% cohesive failure,-   “good” represents 75% to 95% cohesive failure,-   “moderate” represents 50% to 75% cohesive failure,-   “poor” represents less than 50% cohesive failure, and-   “no adhesion” represents 0% cohesive failure or 100% adhesive    failure.

The results are reported in table 1.

Compositions labeled “(Ref.)” are comparative examples.

TABLE 1 Composition (in parts by weight) and properties of Z1 to Z6.¹2,2′- dimorpholinodiethyl ether Z6 Composition Z1 Z2 Z3 Z4 Z5 (Ref.)Polymer P1-1 36.8 36.8 36.8 36.8 36.8 41.8 Polymer P2-1 5.0 — — — — —Polymer P2-2 — 5.0 — — — — Polymer P2-3 — — 5.0 — — — Polymer P2-4 — — —5.0 — — Polymer P2-5 — — — — 5.0 Polymer M 2.8 2.8 2.8 2.8 2.8 2.8Dioctyl adipate 17.1 17.1 17.1 17.1 17.1 17.1 Chalk 20.0 20.0 20.0 20.020.0 20.0 Carbon black 18.0 18.0 18.0 18.0 18.0 18.0 DMDEE¹ 0.3 0.3 0.30.3 0.3 0.3 Adhesion to residual adhesive bead: after wait time 0 minvery good good very good very good very good moderate 5 min very goodgood very good very good very good good 7 min very good good very goodvery good very good moderate 10 min very good moderate very good goodvery good poor

Compositions Z7 and Z8:

Each composition was produced as described for composition Z1 using theingredients specified in table 2 in the amounts specified (in parts byweight), dispensed into an aluminium cartridge with an airtight seal,and stored at room temperature.

Each composition was applied between two silicone-coated release papers,pressed to give a film of thickness 2 mm and stored under standardclimatic conditions for 14 days. After the release papers had beenremoved, rectangular test specimens (75×150 mm) were cut out of thecured film and tested in a QUV weathering device for the time specifiedin table 2, and then the weathered surface was tested for carbon blackstaining by first pressing a transparent adhesive tape onto the surfaceby hand and then sticking it to a white printer paper. Carbon blackstaining was rated as “no” if a light gray stain was then visible,carbon black staining was rated as “moderate” in the case of a dark graystain, and carbon black staining was rated as “severe” in the case of ablack stain.

The results are reported in table 2.

Compositions labeled “(Ref.)” are comparative examples.

TABLE 2 Composition (in parts by weight) and properties of Z7 and Z8.¹Tinuvin 292 ® (from BASF) Z8 Composition Z7 (Ref.) Polymer P1-1 22.327.3 Polymer P1-2 10.0 10.0 Polymer P2-1 5.0 — Diisodecyl phthalate 16.616.6 Stabilizer¹ 1.0 1.0 Chalk 25.0 25.0 Carbon black 20.0 20.02,2′-Dimorpholinodiethyl ether 0.1 0.1 Carbon black staining:  200 h QUVno moderate  500 h QUV no severe 3000 h QUV no severe

Compositions Z9 to Z18:

Each composition was produced as described for composition Z1 using theingredients specified in tables 3 and 4 in the amounts specified (inparts by weight), dispensed into an aluminium cartridge with an airtightseal, and stored at room temperature.

Each composition was tested as follows:

Measures determined for processibility or applicability of thecomposition were expression force, sag resistance and threading. A lowexpression force, a high sag resistance and short threading arerepresentative of good processibility or applicability.

Expression force was determined at 23° C. and at 5° C. A first closedcartridge was stored at 23° C. for 7 days, and a second was stored at23° C. for 6 days and then at 5° C. for 24 hours. Then the expressionforce was measured in each case by means of an expression device(Zwick/Roell Z005), by screwing a nozzle of internal diameter 5 mm ontothe cartridge and then measuring the force required to express thecomposition through the nozzle at an expression rate of 60 mm/min. Thevalue reported is an average of the forces that were measured after anexpression distance of 22 mm, 24 mm, 26 mm and 28 mm. The sag resistanceof each composition was determined by, under standard climaticconditions, applying a triangular bead of width about 8 mm and heightabout 20 mm to a vertical corrugated cardboard surface in such a waythat the triangular bead was arranged as a horizontal strip of width 8mm with a protruding height (=tip) of 20 mm. After curing under standardclimatic conditions, an assessment was made as to whether and how theposition of the bead applied had changed. More particularly, the extentto which the tip, measured from the horizontal position, had saggeddownward was determined. A sag of less than 1 mm was rated as “verygood”, 1 to less than 3 mm as “good”, 4 to 7 mm as “average”, and 8 mmor more as “poor”. A “fluid” composition is defined as one where thematerial applied moved downward, i.e. ran downward, not just at the tipbut also at the base of the triangular bead applied.

Threading was determined for some compositions by measuring the lengthof the thread formed by moving the application cartridge away from thetriangular bead that had been applied for determination of sagresistance.

A measure determined for the processing time (open time) was the skintime (ST). For this purpose, a few grams of the composition was appliedto cardboard in a layer thickness of about 2 mm and, under standardclimatic conditions, the period of time after which no residues remainedany longer on an LDPE pipette used to gently tap the surface of thecomposition was determined.

For determination of the mechanical properties, each composition waspressed between two silicone-coated release papers to give a film ofthickness 2 mm and stored under standard climatic conditions for 14days. After removing the release papers, some test specimens werepunched out and tested as described as follows:

For determination of tensile strength (TS), elongation at break (EaB)and modulus of elasticity at 0.5-5% elongation, dumbbells having alength of 75 mm with a bar length of 30 mm and a bar width of 4 mm werepunched out of the film, and these were tested in accordance with DIN EN53504 at a strain rate of 200 mm/min.

A number of test specimens were also punched out for determination oftear propagation resistance and were tested in accordance with DIN ISO34 at a strain rate of 500 mm/min.

Appearance and gloss were determined visually on the film produced forthe determination of the mechanical properties. “Nice” was used todescribe a nontacky, even film without blisters.

To determine the strength of an adhesive bond, lap shear strength (LSS)for some compositions was determined on glass. For this purpose,composite specimens were produced by bonding two glass plates that hadbeen degreased with isopropanol and pretreated with Sika® Aktivator 100(from Sika Schweiz) in such a way that the overlapping adhesive bond haddimensions of 12×25 mm and a thickness of 4 mm and the glass platesprotruded at the top ends. After the composite specimens had been storedunder standard climatic conditions for 14 d, lap shear strength wastested to DIN EN 1465 at a strain rate of 20 mm/min. As a measure of theheat and hydrolysis stability of the bond, further test specimens wereadditionally stored in an air circulation oven at 100° C. or at 70°C./100% relative humidity for 7 days, cooled down under standardclimatic conditions and tested in the same way. The results are giventhe addition “14d SCC” or “7d 100° C.” or “7d 70/100”.

The results are reported in tables 3 and 4.

Compositions labeled “(Ref.)” are comparative examples.

TABLE 3 Composition (in parts by weight) and properties of Z9 to Z15.¹2,2′- Dimorpholinodiethyl ether n. m. stands for “not measurable” “n.d.” stands for “not determined” Z11 Z13 Z15 Composition Z9 Z10 (Ref.)Z12 (Ref.) Z14 (Ref.) Polymer P1-1 36.8 36.8 41.8 38.2 43.2 39.6 44.6Polymer P2-1 5.0 — — 5.0 — 5.0 — Polymer P2-5 — 5.0 — — — — — Polymer M2.8 2.8 2.8 1.4 1.4 — — Dioctyl adipate 17.1 17.1 17.1 17.1 17.1 17.117.1 Chalk 20.0 20.0 20.0 20.0 20.0 20.0 20.0 Carbon black 18.0 18.018.0 18.0 18.0 18.0 18.0 DMDEE¹ 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Expressionforce [N] 23° C. 809 801 919 653 616 471 249 5° C. 1002 1039 1235 812869 685 468 Sag resistance very very very very moder very poor, fluidgood good good good ate good Threading [mm] 6 14 5 8 11 12 n. m. ST[min] 17 12 17 17 18 17 22 TS [MPa] 8.4 8.6 7.7 8.3 7.6 8.6 8.2 EaB [%]502 557 487 490 466 513 477 Modulus of 6.1 5.7 5.8 5.5 5.2 4.6 4.0elasticity [MPa] Tear propagation 12.3 13.0 11.7 12.0 11.2 11.7 10.0resistance [N/mm] Appearance/ nice/ nice/ nice/ nice/ nice/ nice/ nice/gloss matt slightly glossy matt glossy matt glossy matt LSS [MPa] 14dSCC 4.7 4.8 4.5 4.1 4.5 4.6 4.2 7d 100° C. 5.9 n. d. 5.8 7.0 5.5 5.3 6.87d 70/100 5.2 n. d. 5.3 5.0 3.2 5.2 3.5

Composition (in parts by weight) and properties of Z16 to Z18.Composition Z16 Z17 Z18 Polymer P1-1 36.8 36.8 36.8 Polymer P2-2 5.0 — —Polymer P2-3 — 5.0 — Polymer P2-4 — — 5.0 Polymer M 2.8 2.8 2.8 Dioctyladipate 17.1 17.1 17.1 Chalk 20.0 20.0 20.0 Carbon black 18.0 18.0 18.02,2′-Dimorpholinodiethyl ether 0.3 0.3 0.3 Expression force [N] 23° C.959 633 539 Sag resistance very good very good very good Skin time [min]17 16 16 Tensile strength [MPa] 7.8 6.9 7.4 Elongation at break [%] 472493 482 Modulus of elasticity [MPa] 8.1 5.1 5.6 Tear propagationresistance 13.6 12.5 11.4 [N/mm] Appearance/gloss nice/matt nice/mattnice/matt

1. A moisture-curing composition which is liquid or pasty at roomtemperature, comprising at least one polyether urethane polymer P1containing isocyanate groups and having a content of at least 80% byweight of 1,2-propyleneoxy units in the polyether segment, and at leastone room temperature liquid, hydrophobic polymer P2 containingisocyanate groups, obtained from the reaction of at least one monomericdiisocyanate and a hydrophobic diol having an OH number in the rangefrom 28 to 120 mg KOH/g, wherein polymers P1 and P2 are preparedseparately from one another and polymer P1 and polymer P2 are present ina weight ratio in the range from 70/30 to 98/2.
 2. The moisture-curingcomposition as claimed in claim 1, wherein polymer P1 has an NCO contentin the range from 1% to 5% by weight.
 3. The moisture-curing compositionas claimed claim 1, wherein the isocyanate groups of polymer P1 arederived from diphenylmethane 4,4′-diisocyanate.
 4. The moisture-curingcomposition as claimed in claim 1, wherein polymer P1 is obtained fromthe reaction of at least one monomeric diisocyanate and at least oneoptionally ethylene oxide-terminated polyoxypropylene diol or triolhaving an OH number in the range from 7.5 to 112 mg KOH/g.
 5. Themoisture-curing composition as claimed claim 1, wherein polymer P1 has amonomeric diisocyanate content of not more than 0.5% by weight.
 6. Themoisture-curing composition as claimed in claim 1, wherein polymer P2has an NCO content in the range from 1.5% to 6% by weight.
 7. Themoisture-curing composition as claimed in claim 1, wherein thehydrophobic diol for the preparation of polymer P2 is selected from thegroup consisting of dimer fatty acid-based polyester diols andpoly(1,2-butylene glycol).
 8. The moisture-curing composition as claimedin claim 7, wherein the hydrophobic diol is an amorphous dimer fattyacid-based polyester diol.
 9. The moisture-curing composition as claimedin claim 1, wherein polymer P2 has a monomeric diisocyanate content ofnot more than 0.5% by weight and is obtained from the reaction of atleast one monomeric diisocyanate and the hydrophobic diol in an NCO/OHratio of at least 3/1, followed by removal of a majority of themonomeric diisocyanate by means of a suitable separation method.
 10. Themoisture-curing composition as claimed in claim 1, wherein polymer P2has a viscosity at 20° C. in the range from 10 to 1000 Pa·s, determinedwith a cone-plate viscometer having a cone diameter 25 mm, cone angle 1,cone tip-plate distance 0.5 mm, at a shear rate of 50 s⁻¹.
 11. Themoisture-curing composition as claimed in claim 1, wherein at least onefurther constituent selected from meltable components, blocked amines,fillers, plasticizers, diisocyanate oligomers, catalysts and stabilizersis additionally present.
 12. The moisture-curing composition as claimedin claim 11, wherein it comprises 20% to 60% by weight of polymers P1,0.5% to 10% by weight of polymer P2, 0% to 5% by weight of meltablecomponent, 20% to 60% by weight of fillers, 0% to 35% by weight ofplasticizers, and optionally blocked amines, diisocyanate oligomers,catalysts or stabilizers.
 13. The moisture-curing composition as claimedin claim 1, wherein it comprises carbon black.
 14. The moisture-curingcomposition as claimed in claim 1, wherein it comprises less than 0.1%by weight of monomeric diisocyanates.
 15. A method of bonding orsealing, comprising the steps of (i) applying the moisture-curingcomposition as claimed in claim 1, to a first substrate and contactingthe composition with a second substrate within the open time of thecomposition, or to a first and to a second substrate and joining the twosubstrates within the open time of the composition, or between twosubstrates, (ii) curing the composition by contact with moisture.
 16. Anarticle obtained from the method as claimed in claim 15.